I believe the reason for this isnthat there is already a role that is reaponsible for the whole circle -> the Lead Link.
The objector can bring it to the lead link to introduce a new tension to fix this if the Lead Link believes it is harming or moving the circle backwards. The Lead Link can ofcourse do this immediately after hearing that the objection was dropped because it was 't limiting the objector's role.
I also often wonder about this myself,because there is somehow this selfish hints to it, and we all want people who thinks about the whole circle ahead of their own roles actually.
Anyways, that's the way I understand it